From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Google-Smtp-Source: AB8JxZrttQ4P+xEvsvGsx0jejG3Nws4TsUHZQ8qKYwxuoyU6qmt5SMrjg7S4oGhOT5bAGi6lC3rb ARC-Seal: i=1; a=rsa-sha256; t=1525116382; cv=none; d=google.com; s=arc-20160816; b=kBAIvh7iu/RxRBpeibXDlyV22nu2fWSRDzki2PR14sygfEJJHGC0Xx1SSOGKhgNMdx 6u19ShRtKXVRuSjAOmgQjvH285JGDuLe5GHXyPpdytaYLOSIAwAJ97gBJ1D6zne6Q0ol BXUac2cVuCuMMiRxyLibfL5wX5qioRon6UUO5bTr+5s27v2IFyhuzJjvHWcsWdjnJr8p TS4yPgi1G8KbQXf8IXHRmIGs+XCW/AQzso8DK6uiiTxFwH+PHb1Lsp8cDgVmUqpI3FC7 Ab/dAiEPAIyruv913b/TrVVHdorwyDZWi9DMHw69M1iwY/hOLR56a2s44N1rrIhK04Y0 iCJg== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=arc-20160816; h=mime-version:user-agent:references:in-reply-to:message-id:date :subject:cc:to:from:dmarc-filter:arc-authentication-results; bh=Z6nCINH4TDQ2HvVuyaCN8BsIo0cCVla1nyYda9rteV4=; b=panGaDTNpvDLEo9rBaXt58sMGlWS0Uy3vAzXuq3HkjKLumro0pwAomC0FmCBeOL0c9 AAVPFsIbp7niPxWpIBYPMPE1Ntv8+0GSvTvyVb6fJFmsFQImxgAviaBNeAxA2T7GAsHr ENfzrsiIB6G179xE5S26SwGnLhcz9H7c6I5XLRh6GIdyNhW/BkygHBTOw2IJAahLWYwC PjAyoVaQ+z171LuZUHDBMwdPMDPfHFaOW8SGin9xCXJtM/51LBAfEF0tDDSXjvlwI4NE MPRaHqAlMmTVxrmnxwb3Pq+T0K1yxlcHic8+F5LQBoBGFX5HxeQXDokFDJyO+T8o4b78 kV5w== ARC-Authentication-Results: i=1; mx.google.com; spf=pass (google.com: best guess record for domain of srs0=k66p=ht=linuxfoundation.org=gregkh@kernel.org designates 198.145.29.99 as permitted sender) smtp.mailfrom=SRS0=K66P=HT=linuxfoundation.org=gregkh@kernel.org Authentication-Results: mx.google.com; spf=pass (google.com: best guess record for domain of srs0=k66p=ht=linuxfoundation.org=gregkh@kernel.org designates 198.145.29.99 as permitted sender) smtp.mailfrom=SRS0=K66P=HT=linuxfoundation.org=gregkh@kernel.org DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 9450322DC0 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=linuxfoundation.org Authentication-Results: mail.kernel.org; spf=fail smtp.mailfrom=gregkh@linuxfoundation.org From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Alain Magloire , Gerd Hoffmann , Dave Airlie , Sean Paul Subject: [PATCH 4.9 19/61] drm/virtio: fix vq wait_event condition Date: Mon, 30 Apr 2018 12:24:22 -0700 Message-Id: <20180430183952.956075938@linuxfoundation.org> X-Mailer: git-send-email 2.17.0 In-Reply-To: <20180430183951.312721450@linuxfoundation.org> References: <20180430183951.312721450@linuxfoundation.org> User-Agent: quilt/0.65 X-stable: review MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 X-getmail-retrieved-from-mailbox: INBOX X-GMAIL-LABELS: =?utf-8?b?IlxcU2VudCI=?= X-GMAIL-THRID: =?utf-8?q?1599200400304649329?= X-GMAIL-MSGID: =?utf-8?q?1599200435510535117?= X-Mailing-List: linux-kernel@vger.kernel.org List-ID: 4.9-stable review patch. If anyone has any objections, please let me know. ------------------ From: Gerd Hoffmann commit d02d270014f70dcab0117776b81a37b6fca745ae upstream. Wait until we have enough space in the virt queue to actually queue up our request. Avoids the guest spinning in case we have a non-zero amount of free entries but not enough for the request. Cc: stable@vger.kernel.org Reported-by: Alain Magloire Signed-off-by: Gerd Hoffmann Reviewed-by: Dave Airlie Link: http://patchwork.freedesktop.org/patch/msgid/20180403095904.11152-1-kraxel@redhat.com Signed-off-by: Sean Paul Signed-off-by: Greg Kroah-Hartman --- drivers/gpu/drm/virtio/virtgpu_vq.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) --- a/drivers/gpu/drm/virtio/virtgpu_vq.c +++ b/drivers/gpu/drm/virtio/virtgpu_vq.c @@ -324,7 +324,7 @@ retry: ret = virtqueue_add_sgs(vq, sgs, outcnt, incnt, vbuf, GFP_ATOMIC); if (ret == -ENOSPC) { spin_unlock(&vgdev->ctrlq.qlock); - wait_event(vgdev->ctrlq.ack_queue, vq->num_free); + wait_event(vgdev->ctrlq.ack_queue, vq->num_free >= outcnt + incnt); spin_lock(&vgdev->ctrlq.qlock); goto retry; } else { @@ -399,7 +399,7 @@ retry: ret = virtqueue_add_sgs(vq, sgs, outcnt, 0, vbuf, GFP_ATOMIC); if (ret == -ENOSPC) { spin_unlock(&vgdev->cursorq.qlock); - wait_event(vgdev->cursorq.ack_queue, vq->num_free); + wait_event(vgdev->cursorq.ack_queue, vq->num_free >= outcnt); spin_lock(&vgdev->cursorq.qlock); goto retry; } else {